Self aligning coupling



June 14, 1960 R. w. HORNING 2,940,786

SELF ALIGNING COUPLING Filed Jan. 20, 1958 2,940,786 Patented June 14, 1960 SELF ALIGNING COUPLING Rodney W. Horning, Manhattan Beach, Calif., assigner to Northrop Corporation, Beverly Hills, Calif., a corporation of California Filed Jan. 20, 1958, Ser. No. 709,937

3 Claims. (Cl. 287-87) The present invention relates to coupling devices and more particularly yto a rigid self-aligning coupler assembly adapted to transmit true linear vibrations from an exciter to a fixture or the like.

Prior art coupling devices, utilized to transmit linear vibrations from an exciter to a fixture or the like, are either of rigid or flexible construction, the latter construction .functioning to compensate for limited linear or angular misalignments `between the exciter and fixture. Prior art devices of the above types quite frequently function in a manner to provide unsatisfactory and objectionable results, Quite frequently the above devices do not transmit true vibrations as originated by the exciter and undesirable and objectionable moments may be introduced into the coupler which in turn further distort the vibrations as originated yby the exciter.

Accordingly it is an object of the present invention to provide a coupler assembly adapted to provide a rigid connection between two components or .the like and which automatically adjusts itself to compensate for Flimited angular, linear and rotary misalignment which may occur or be present between the components.

Another object is to provide a coupler assembly which will transmit vibrations between two components or the like without introducing undesirable moments in the coupler assembly and without distorting the vibration wave form as originated by one of the components.

Another object is to provide a coupler assembly which is of rigid construction, which is self-aligning, which Will transmit true linear vibrations from one component to another, which is simple in design and rugged in construction and which is economical to manufacture.

Although the characteristic features of the present invention are particularly pointed out in the `appended claims, the invention itself yalso the manner in which it may be carried out, will be better understood by referring to the following description taken in connection with the accompanying drawings forming a part of this specification and in which:

Figure l is an exploded view of the coupler assembly as disclosed herein.

Figure 2 is a sectional view of the assembly as indicated by the line 2 2 in Figure 3, the components of the assembly being in their aligned or centered and assembled relation.

Figure 3 is an end view of the coupler assembly shown in Figure 2.

Figures 4 and 5 are sectional views similar to the view shown in Figure 2 but with portions of the assembly vertically and angularly misaligned, respectively.

Referring now to the drawings, the various components of the coupler assembly 11 include a tension-compression member 12, a pair of end bell members 14 and 16 and a pair of nut members 17-17. The member 12 consists of a compression load member 18 and a tension rod 19. For reference purposes the bell members are here- The tension-compression member 12 may be of unitary construction or it may be fabricated by securing the member 18 in a rigid and ixed relation on the rod 19 at its midpoint as best as seen in Figures 2, 4 and 5. In the embodiment shown the rod is circular in cross-section although ythis need not necessarily be the case. The axis o-f the rod is .identified by the line A-A. The load member 18 is similar in construction to that of a throwing discus having its axis coincident with the axis A-A. The side faces 21-21 of the member 18 constitute identical spherical surfaces each having a radius R1 as shown in Figure 2. The spheres, of which the surfaces 21-21 constitute a part, have their centers located at the respective ends of the rod 19 and on the axis A--A. The outer peripheral surface of the member 18 is cylindrical as indicated by the numeral 22, however, this surface may be dispensed with in lwhich case the spherical surfaces 21-21 will continue until they intersect.

As mentioned above, the bell members 14 and 16 are of identical construction, therefore, a description of one will apply tothe other and for purposes of illustration the right-hand member 14 lwill be described in detail. This inafter referred to as right-hand and left-hand members 14 and 16, respectivel although their construction is identical.

member is generally of cylindrical configuration having one end which presents an annular plane surface 23 and the other end resembles a truncated cone which presents an annular plane surface 24, an annular sloping surface 26, and a concave spherical surface 27.

The concave spherical surface 27, having the same radius R1 as the spherical surfaces Ztl- 21, is provided in the .truncated portionvof the member 14 and opens on the surface 24. The end of the member 14, containing .the surface 23, is indented and terminates in a spherical surface 28 havinga radius R2 as shown in Figure 2. The centers .of the surfaces 27 and 23 coincide to render these surfaces concentric and deiine a wall 29 of non-varying thickness. Indentations 31 and bores 32 are provided in the member-14 substantially as shown and provide means wherebyrthe Vlatter may be secured to structure (not shownlin a manner presently explained. A central aperture 33 is provided in the wall 29 and is somewhat larger in diameter than the diameter of the rod i9 for a purpose which will be-apparent presently.

The nut members 17-17 are substantially of conventional construction except that one of their end faces 34 is concave and constitutes a spherical surface having a. radius R2 and therefore has the same curvature as the surface 28.

in assembling the coupler 11 a bell member is positioned on each side of the compression member 18 with the respective ends of the rod 19 extending through the apertures 33. So positioned lit will be apparent that the respective surfaces 21 and 27 will mate with each other in iirm contacting relation. The nut members 17-17 are now secured on respective ends of the rod 19 in a conventional manner `by means ofthreads .formed on an exciter (not shown) and a fixture (not shown)the latter having an instrument orthe like mounted thereon which is to be subjected to linear vibrations. A

Referring lnow to Figure 2 it'will be seen that all components of the coupler assembly 11 are symmetrically positioned with respect to the axis A-A of the rod 19.

In this position, hereinafter referred to as thercentered' it will be noted that^ positionv of the coupler assembly,

coupler as# sembly may be utilized to provide a connection between the. annular surfaces 24-24 anda plane passing through the center Yof the compression member 18, as indicated by the line B-B in Figure 2, are normal to the axis AY-Y-Af' `It willgalso V,be noted that the rod 1911is off .suchV aflengththat :both of its ends are located inboard with respect to the` annularsurfaces 23a-23;ffln :this flgure,`

4 i Y invention is not limitedV to the specific features shown, but that the means and construction herein disclosed comprise a preferred form of putting the invention into effect,

itpgwill beapparent 'that-if an exciter `-is attached-fogne I othe bell members' and Ya 'holding fixture to theother the Y assembly 11w will :provide a rigid connection therebetween andA linear Yvibrations originating Withthe eXciter-willbe transf/erred in equal magnitude and without distortion Yto theigiixture'alog the axis A-AL ,i f i l euliigureit will be Vseenthat one of Ythe-bell membe'rsg23rrhas 4beenY linearly displaced' an amount X'witltlY yrespectto the other. Under the conditions prevailingpin Eigure14-itisto ibe'understood'that the bell members 114 and l16A are attached to frigid structure causing them to move'in true vertical directions YWhile being displaced thedistance X. In this figure it will also be assumed that: theleft-hand bellinie'mberiZS has been causedpto move vertically upward the distance X Whiletherighthandfbellxmember 23Vretaned its 'originalposition Y 1, In viewiof the above it may befurther assumed that. afholding'xture (not shown) is attached to the left-hand bell'rneniber While anexciter (not shown) Ais attached to theLright-hand' bell member.V Underrthese conditions vit and the invention 1s therefore claimed in any of its forms or modigcations within the legitimate and valid vscope of the appended claims. f

What is claimed is: t 1. A self-aligning coupler 'assembly' comprising: an elongated member-including 'a Ydisc-like lcenter portion and rod-like end portions; .said'centerrportion being characterized by including a pair of convexfsphericalsurwill" be apparent that the aforementioned lixturehas--V shiftedl upward during a vibrating Ytest run. As the lefthand'bell member 23 is caused to shiftupward the lower portion of its sphericalfsurface 27-will exerta dominating forcefon the lower left spherical surface 21 ofthe memberV 18 ('as'viewed in rFigure 4). VThis force lwill causethe member 18 to rotateron the spherical surface T27 ofV theiright-hand bell member 14 with the result that the tension-'compression member V1li will rotate through an" angle OC aboutthe left-hand end ofthe rod 19. -This movement 4and realignment of parts 'allows the 'annular' surfaces 23-231tomaintain their'paralle'l relation. 'Y

iDilring Athe Vabove movement4 and Vrealignment of parts f itwill'be seenthatth'e apertures 33-33 were frsuiiicientsizeito'allowt-he 'rod 19 fto move through-'the angle"OC .withoutlnterference f Also' the end of the Yrod 19 remains inboard with respect to "the annular surfaces 23-23[ 'a'nd,

therefore, does not interferevvith theattachingportions l of either the exciter or xturel In thisinstanee, although Vthe-'annularY surfaces 2.3-2.3 maintain their parallel relation, Lit will be apparent that there arel no undesirablev moments introduced in the coupler assemblyV and the latter will'transrnit linear vibrations from theV exciter to '50 the xture Without distortions.

In FigurerS the right-hand bell member 14 has been` Anorfred through an angle Vqs with respect to the left-hand bell'member. kIn this instance the movement 'and re-Y alignment `of parts is quite similar to thatdescribed in connection with-Figure -4 and a'detailed'description of this movement is, therefore, deemed unnecessary. `It will also`be-apparent that in this instance the movementkand realignment of parts has not introduced anyiu'ndesirable Y momentspin the VcouplerA assembly `while a rigidjconnec-Y tion is maintained between the two components'whichrare alpairo'f'end members each'fhaving'a circular aperture faces the centers of -curvature'of which are located on the axis of said disc-like center portion and'on opposite sides of a plane passing 'throughthe-'center of said disclike center portion and is perpendicular to the axis of said disc-like center portion; a pair of end bells each liavingfacircular Vaperture'"formed :thereinxofV adiameter exceeding the greatest' cross=sectionalmeasure-Y ment of .saidend portions; said end .bells being further characterized in that each .includes concentric convex and concave spherical. surfaces the centersV of Ycurvature of`whi'ch are located-'on the `axislof the respective 'aperture .formed therein; said end 'bellsbeing mounted on Vsaid 'memberfon each side of 'said disc-.likev center portionvvithfsaidend kportions extending through said aperof curvature of which lie on'the axis, of said discflike center portion 'and on opposite Vsides Voi a plane passing through theA centerfor' saidldisc-like Vcenter portion ,and is` perpendicular to the axis of said-disc-like center portion;

formed'thereinf-'a diameter exceeding the diameter of saideridportions;YV ,said end membersvbe'ing furtheijvchar-v aeter'ized vin that-:each includes concentric convex p and concavespherical surfaces the centers Yof curvatureof which lie on the axis of the respective aperture formed therein;V saidend members being mounted Von Yeachv side o fv said disc-,like center portion with said concave surfaces thereof contacting the convexY surfaces of said disc-like center portion and Y With'said end portions extending through` ,saidapertures and a pair ofnut members, each defining a'concave spherical surface of less -extentthanvrespective t convex surfaces kof said end members, securedon said end vportions with the concave surfaces of said nut mem-A bers contacting the'respective convex surfaces of said en d members. y Y. Y Y V ,n

"3'. A Selb-aligning 'coupler :assembly as set forth in clanigZt'further cliaract'erize'd inthat theboundaries of connectedby the assembly; Accordingly, ifltheicou'pl'er assembly is utilized'to transmit linear vibrations from an exciterjto a iixture, linearvibrations willV be transmitted yfrom-jthe exciter to the'iixture Without distortion. In .view of the foregoing discussionandpV description ofV v the coupler assembly 11, it Ywilljbe apparent Vtlatthe l assembly will alsoserve to provide a rigid connection in instances where linear and angular misalignment are both Y present. Under these conditions as inpreviousV instances Y undesirableV moments will notibe introduced in the `coupler asseinbly'llY and linearY vibrationshwill be transmitted Without distortion. Y ,Y J Y Y While in order to Vcomply with the'statute, the`invention 1hasfbeen described inlanguage more or less specific Y as-to'structuralfeatures; itgisrto beunderstood that the said sphericalsurfacesjon said disc-like center portion constitute, circles of prgdeterminedgdiametel'sland the boundaries of saidA concave surfaces on' said endmem- Vbersr.,constitute c irclesrofV less diameter thana`respective diameterrdeining `the, spherical surfaces 'on saidV discf like centerportion; ,Y Y Q -References'Cited VVtlietle offthis patenti 

